ChatGPT can be a useful tool for developing thank-you notes as it is a large language model that has been trained on vast amounts of text data. It can generate a wide range of language patterns and structures, making it easy to generate thank-you notes with personalized messages. By providing ChatGPT with some initial information, such as the reason for the thank-you note, the recipient's name, and some additional details, it can generate a custom thank-you note in a matter of seconds.